Even before the numbers were released, it was obvious that this past weekend's Anime Expo had brought in more people than normal. There were blocks of people trying to move through the aisles in the exhibit hall. The L.A. Convention Center's South Hall lobby was practically overflowing with cosplayers and the people who wanted photos with them. In fact, 61,000 unique individuals made their way to the convention, which is dubbed the largest anime, manga and Japanese culture convention in North America. That's up from 52,000 unique attendees in 2012 and it's enough growth to make many an AX regular wonder what was happening.

Marc Perez is the CEO and President of Society for Promotion of Japanese Animation. That's the non-profit responsible for Anime Expo, as well as the industry event Project Anime and San Diego convention Anime Conji. He's been with AX for 11 years, having started out as a volunteer AV technician, and was a convention attendee before that. Perez explained three likely factors in this year's attendance upswing: famous guests, a new hit anime series called Attack on Titan and marketing.

This is not a drinking game. Seriously.

Liz Ohanesian

Certainly, there were some major draws amongst this year's roster of guests. Perez mentions Porno Graffiti, a popular band from Japan, as an example. The Anime Expo team also launched successful marketing campaigns, letting people know about new features at the convention. Perez points out the Cosplay Participation Zone as an example. That was a space where several prop-heavy sets were installed for photo ops.

I was curious about Attack on Titan's influence on the convention, particularly considering that George Wada, who produces the show, appeared at the event. Attack on Titan is a new anime that you can watch online via Crunchyroll, Hulu or Funimation. It's about people who have to deal with giants. Every year at Anime Expo there are a couple new-ish shows that prove to be exceptionally popular with the crowd -- last year the honors went to Tiger & Bunny and Puella Magi Magica Madoka -- but this is different. The response to Attack on Titan was intense. There were so many people wearing costumes from the show that they far overshadowed even old standbys like Bleach and Naruto.

Meanwhile, inside the karaoke room, people kept shouting "Jäger!" I thought it had to do with alcohol. It doesn't. A friend of mine explained the joke and let me post her response on Instagram. In a nutshell, shouting "Jäger!" is an Attack on Titan thing too.

"It's been a few years since we've seen something really large that's anime based," says Perez. "I think that Attack on Titan is starting to pick up not just with anime fans, but is spreading on to regular animation fans and the general public."

I asked Perez when he last saw an anime grab such a strong hold of the crowd. His answer: Cowboy Bebop, one of the most famous anime series of all time.

But there must be more to Anime Expo's popularity than just these reasons. After all, it's not the only convention that has seen a lot of success in recent years. San Diego Comic-Con has become a beast of an event. New conventions, like Stan Lee's Comikaze, have been drawing solid crowds. Even a significantly smaller event, Gallifrey One, sold out this year.

Right now, conventions overall are becoming increasingly popular. Many are drawing bigger crowds. Plenty are experiencing more attention from mainstream press. Could it be, at least in part, because of the costumes?

Visual storytelling is important, particularly now, as our eyes move away from print and towards our laptops, tablets and smart phones. At a convention, many of the most compelling images you will see are of cosplayers. The fact that they can transform themselves into recognizable fictional characters makes them hard to miss. And as their electronic images continue to be shared, retweeted or reblogged, the curiosity of others outside the scene is piqued.

Perez acknowledges that cosplay is a factor in Anime Expo's current success. "I think that speaks volumes to the interactive enjoyment that people get," he says. Cosplay goes beyond looking good. In my recent story, "A Fan Convention Through the Eyes of a Single Cosplayer," I likened the experience to meeting your favorite Disneyland characters. It's a truly gleeful experience when you find some trace of your favorite fictional world in the real one. Conventions are giving people that and then those experiences are shared over and over again.

Undoubtedly, social media is playing a big role in the popularity of conventions, as people are able to update friends on shenanigans in real time. Anime Expo itself has a hefty Facebook presence. It has pages in English, Japanese and Spanish. Perez also notes that its Tumblr presence is gaining a lot of steam, more so than its Twitter feed. Since its primary demographic is ages 16-26, that makes a lot of sense. "Tumblr seems to be a much younger crowd, but it's more vocal and more feeling and experience-based," he says.

With that in mind, it seems that the pure rush of emotion that comes from being at a convention is spreading fast. It will make you wonder what next year's event will have in store.